stock 99 lightning feeling sluggish

[rustyruststang8]

I raced my 99 lightning vs my near stock 91 5.0 5spd mods are (CAI, and full exhaust)
we raced a 15mph rool, 45 mph roll, and 2 times from a dig and each time my 91 coupe pulled 2-3 car lengths. this just doesn't seem normal to me especially considering my coupe has 240,000 miles.


now the lightning doesn't have any check engine codes or anything and it does build about 9 psi of boost. but I did notice it had autolight platinum plugs, I changed out the front four with ngk tr6 because I had a misfire code come on and I have not don't the rear four yet. I don't know if that will make a huge difference.

 

[flip_86]

Depending on the condition of the plugs it could be significant, also check that the intercooler pump is runing

 

[flip_86]

When was the last time the fuel filter was changed?

 

[Dusten]

I raced my 99 lightning vs my near stock 91 5.0 5spd mods are (CAI, and full exhaust)
we raced a 15mph rool, 45 mph roll, and 2 times from a dig and each time my 91 coupe pulled 2-3 car lengths. this just doesn't seem normal to me especially considering my coupe has 240,000 miles.


now the lightning doesn't have any check engine codes or anything and it does build about 9 psi of boost. but I did notice it had autolight platinum plugs, I changed out the front four with ngk tr6 because I had a misfire code come on and I have not don't the rear four yet. I don't know if that will make a huge difference.

Stock motor needs stock plugs. Those tr6s are going to do nothing good.

Check the basics, is the ic pump working? It's the ic clean? That said the 99s were only a 14 second truck.

 

[black99lightnin]

Stock motor needs stock plugs. Those tr6s are going to do nothing good.

Check the basics, is the ic pump working? It's the ic clean? That said the 99s were only a 14 second truck.

13.8-14.1 stock. But a stock 91LX isn't any faster or could be quite slower depending on gearing.

OP, heat will absolutely kill a Lightning. You could easily lose .5ths from cold weather to hot weather.

 

[Dusten]

13.8-14.1 stock. But a stock 91LX isn't any faster or could be quite slower depending on gearing.

OP, heat will absolutely kill a Lightning. You could easily lose .5ths from cold weather to hot weather.

That's what I was getting at. It's not like he should be destroying that Fox. Any amount of heat soak or mechanical issues and it's going to look one sided.

 

[rustyruststang8]

i just did the fuel filter. where is the ic pump and when does it come on?

 

[Dusten]

The ic pump is computer controlled. You can pull the relay and jump it. This will turn it on. Then just open the reservoir and look for fluid movement

 

[Dusten]

 

[black99lightnin]

i just did the fuel filter. where is the ic pump and when does it come on?

Under the bumper behind the heat exchanger. If you try what Dusten instructs you and it doesn't work, lightly bang on it and see if it comes on. If it does, then it is going bad and needs to be replaced.

 

[rustyruststang8]

sounds good. I just read a good write up on how to clean the ic so I might be doing that soon as well. why are the 99 L so much slower then the 01 and up? is it just the 20hp and the gear change?

 

[black99lightnin]

01+ had a larger maf and better gearing. You can buy the mafs new for $100. But when you do make sure to get a tune from a reputable Lightning tuner. In cold air you can run mid 12's with 90mm maf, 4lb lower, tune, and Dr's.

 

[Dusten]

sounds good. I just read a good write up on how to clean the ic so I might be doing that soon as well. why are the 99 L so much slower then the 01 and up? is it just the 20hp and the gear change?

Tune, gears.

 

[rustyruststang8]

where do you get them new for $100?

 

[black99lightnin]

http://www.buyfordracingfromdpm.com/products/90MM-LIGHTNING-AIR-METER.html

 

[Fox7upStang]

I just did this this afternoon, but I found a great way to keep the ic pump running when you turn the key on. Just run a ground to the correct side of the relay and it will turn on when you turn the key.